Difficulty: Easy
Correct Answer: The periodic time of a particle in SHM is the time taken for one complete oscillation.
Explanation:
Introduction / Context:This question checks your conceptual understanding of simple harmonic motion (SHM) — a foundational topic in engineering mechanics and physics. Knowing which definitions and properties are correct helps when analyzing springs, pendulums, and vibration problems.
Given Data / Assumptions:
Concept / Approach:The periodic time (or period) T is the time taken to complete one full oscillation and return to the same dynamic state. For ideal SHM, T = 2π / ω. Velocity and acceleration vary sinusoidally: velocity is maximum at the mean position and zero at extremes; acceleration is zero at the mean and maximum in magnitude at extremes.
Step-by-Step Solution:
Identify the precise definition: “periodic time” is time for one complete cycle.Check dependence on ω: T = 2π / ω, so T is inversely proportional to ω, not directly proportional.At the mean position, x = 0 → v = ωr (maximum), a = 0.At extremes, v = 0 and |a| = ω^2 r (maximum).Verification / Alternative check:Using energy: total energy E = (1/2) k r^2 is constant; kinetic energy is maximum at the mean where speed is maximum, consistent with the kinematics above.
Why Other Options Are Wrong:
Common Pitfalls:Confusing where velocity versus acceleration are maximum; mixing up period and frequency relations.
Final Answer:The periodic time of a particle in SHM is the time taken for one complete oscillation.
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